function copyToClipboard(txt) {
    if (window.clipboardData) {
        window.clipboardData.clearData();
        window.clipboardData.setData("Text", txt);
    } else if (navigator.userAgent.indexOf("Opera") != -1) {
        window.location = txt;
    } else if (window.netscape) {
        try {
            netscape.security.PrivilegeManager.enablePrivilege("UniversalXPConnect");
        } catch (e) {
            alert("被浏览器拒绝！\n请在浏览器地址栏输入'about:config'并回车\n然后将'signed.applets.codebase_principal_support'设置为'true'");
        }
        var clip = Components.classes['@mozilla.org/widget/clipboard;1']
                .createInstance(Components.interfaces.nsIClipboard);
        if (!clip) {                                                               
            return;
        }
        var trans = Components.classes['@mozilla.org/widget/transferable;1']
                .createInstance(Components.interfaces.nsITransferable);
        if (!trans) {
            return;
        }
        trans.addDataFlavor('text/unicode');
        var str = new Object();
        var len = new Object();
        var str = Components.classes["@mozilla.org/supports-string;1"]
                .createInstance(Components.interfaces.nsISupportsString);
        var copytext = txt;
        str.data = copytext;
        trans.setTransferData("text/unicode", str, copytext.length * 2);
        var clipid = Components.interfaces.nsIClipboard;
        if (!clip) {
            return false;
        }
        clip.setData(trans, null, clipid.kGlobalClipboard);        
    }
    alert("感谢您对工商网站的支持，本网页地址已经复制到剪贴板中。\n您可以通过邮件等方式发送给您的朋友。");
}